In Macedonia, people watch the sunrise from a rocky crest filled with astronomical markers at the megalithic observatory Kokino on Friday — the day of the summer solstice. NASA ranks Kokino as the fourth-oldest observatory in the world.

Revelers arrive to attend the annual celebration of the summer solstice at Stonehenge, southwest of London.

Kerim OktenEPA /LANDOV

Originally published on June 21, 2013 11:42 am

Whether you like it or not, the day will be bright. For those of us in the northern hemisphere, today is the summer solstice, which marks the longest daylight period of the year and the official start of summer.

The summer solstice happens when the sun is shinning directly overhead at midday at varying latitudes. That happened at 1:04 a.m. on Friday for the East Coast and at 10:04 p.m. Thursday for the West Coast.

"The solstice is split into separate days for different time zones this time around simply because the solstice happens to occur so close to midnight," Weather.com explains.

All that to say, welcome summer! We'll leave you with a few sunny images of how people marked the occasion across the globe: